Wixel, anyone using them?

You should be able to cobble the same system together with an ESP8266 and any other Arduino.
Connect the ESP8266 to the ICSP header on the Arduino and write a sketch for it that allows you to receive a hex file by Bluetooth or over WiFi and push it to the Arduino by ICSP, otherwise it can operate as a Bluetooth/WiFi antenna for the Arduino.
Pretty sure that would do it, but I have to test the concept to be certain.